I read a story that a router bit jumped out of a router table and hit the face. I thought it was a short article in FWW, but not sure.
And similar thing happened to me yesterday.
I was making a 1/4 wide, 3/8 deep groove for a 8x12 inch cabinet door frame to accept a panel.
It was a usual spiral bit and a PC fixed based router attached to a table.
After a while, I started to experience chatter and stopped the router.
What I found after I lifted up the wood was the bit almost falling off from the router and dug deeply into the wood.
I suspect the upcut spirals tend to be pulled into the material?
Similar to what the writer of the FWW story said, I believe I tightened the collet as usual. Not extremely tight but with a good squeeze of two wrenches. I guess better than what we can easily do with the usual one-wrench operation for many modern routers.
It is a bit of worrisome to experience like this without a clear idea about the cause.
I wonder if you had ever experienced something similar and share your idea about the causes and prevention.
p.s.: I always lift bits in the collet for a small amount, as suggested.